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1.
Molecules ; 26(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652887

RESUMEN

Although several natural plants and mixtures have been known and used over the centuries for their antibacterial activity, few have been thoroughly explored in the field of dentistry. Thus, the aim of this study was to enhance the antimicrobial activity of a conventional glass ionomer cement (GIC) with natural plant extracts. The effect of this alteration on the bond strength and film thickness of glass ionomer cement was evaluated and related to an 0.5% chlorohexidine modified GIC. Olive leaves (Olea europaea), Fig tree (Ficus carica), and the leaves and roots of Miswak (Salvadora persica) were used to prepare an alcoholic extract mixture. The prepared extract mixture after the evaporation of the solvent was used to modify a freeze-dried glass ionomer cement at three different extracts: water mass ratios 1:2, 1:1, and 2:1. An 0.5% chlorhexidine diacetate powder was added to a conventional GIC for the preparation of a positive control group (CHX-GIC) for comparison. The bond strength to dentine was assessed using a material-testing machine at a cross head speed of 0.5 mm/min. Failure mode was analyzed using a stereomicroscope at 12× magnification. The cement film thickness was evaluated in accordance with ISO standard 9917-1. The minimum number of samples in each group was n = 10. Statistical analysis was performed using a Kruskal-Wallis test followed by Dunn's post hoc test for pairwise comparison. There was a statistically insignificant difference between the median shear bond strength (p = 0.046) of the control group (M = 3.4 MPa), and each of the CHX-GIC (M = 1.7 MPa), and the three plant modified groups of 1:2, 1:1, 2:1 (M = 5.1, 3.2, and 4.3 MPa, respectively). The CHX-GIC group showed statistically significant lower median values compared to the three plant-modified groups. Mixed and cohesive failure modes were predominant among all the tested groups. All the tested groups (p < 0.001) met the ISO standard of having less than 25 µm film thickness, with the 2:1 group (M = 24 µm) being statistically the highest among all the other groups. The plant extracts did not alter either the shear bond strength or the film thickness of the GIC and thus might represent a promising additive to GICs.


Asunto(s)
Antiinfecciosos/química , Cementos Dentales/química , Cementos de Ionómero Vitreo/química , Extractos Vegetales/farmacología , Antiinfecciosos/farmacología , Clorhexidina/química , Clorhexidina/farmacología , Cementos Dentales/farmacología , Dentina/química , Dentina/microbiología , Ficus/química , Cementos de Ionómero Vitreo/farmacología , Humanos , Ensayo de Materiales , Olea/química , Extractos Vegetales/química , Hojas de la Planta/química , Raíces de Plantas/química , Salvadoraceae/química , Resistencia al Corte , Propiedades de Superficie
2.
Sci Rep ; 10(1): 22312, 2020 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-33339861

RESUMEN

Plants may contain beneficial or potentially dangerous substances to humans. This study aimed to prepare and evaluate a new drug delivery system based on a glass-ionomer-Brazilian pepper extract composite, to check for its activity against pathogenic microorganisms of the oral cavity, along with its in vitro biocompatibility. The ethanolic Brazilian pepper extract (BPE), the glass-ionomer cement (GIC) and the composite GIC-BPE were characterized by scanning electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and thermal analysis. The BPE compounds were identified by UPLC-QTOF-MS/MS. The release profile of flavonoids and the mechanical properties of the GIC-BPE composite were assessed. The flavonoids were released through a linear mechanism governing the diffusion for the first 48 h, as evidenced by the Mt/M∞ relatively to [Formula: see text], at a diffusion coefficient of 1.406 × 10-6 cm2 s-1. The ATR-FTIR analysis indicated that a chemical bond between the GIC and BPE components may have occurred, but the compressive strength of GIC-BPE does not differ significantly from that of this glass-ionomer. The GIC-BPE sample revealed an ample bacterial activity at non-cytotoxic concentrations for the human fibroblast MRC-5 cells. These results suggest that the prepared composite may represent an alternative agent for endodontic treatment.


Asunto(s)
Anacardiaceae/química , Cementos de Ionómero Vitreo/síntesis química , Boca/efectos de los fármacos , Extractos Vegetales/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Brasil , Fuerza Compresiva , Frutas/química , Cementos de Ionómero Vitreo/química , Cementos de Ionómero Vitreo/farmacología , Humanos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Boca/química , Boca/microbiología , Extractos Vegetales/farmacología , Espectroscopía Infrarroja por Transformada de Fourier
3.
Niger J Clin Pract ; 23(8): 1073-1078, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32788484

RESUMEN

Aims: The aim of this study was to compare the retention of different luting agents used with implant-supported restorations. Materials and Methods: A total of 90 custom metal frameworks and copings were prepared and divided into six different luting agent groups (n = 15/group): polycarboxylate cement (PC), resin-modified glass-ionomer cement (RMGIC), two self-adhesive resin cements (SARC), copper-ion zinc-phosphate cement (CZPC), and non-eugenol temporary resin cement (TRC). After sandblasting with 50 µm Al2O3, the copings were cemented on frameworks and stored in artificial saliva for 48 h at 37°C and thermocycled between 5-55°C for 37,500 cycles. Samples were subjected to tensile testing by a universal testing machine, and data were statistically analyzed. Results: The differences between the retention values of types of cement were significant (P < 0.05). The maximum retention value was calculated for CZPC (755,12 ± 55 MPa) while the lowest value was for TRC (311,7 ± 61 Mpa). Conclusion: Neither of the tested cement had superiority over another to ensuring retention. The types of cement presented were meant to be a discretionary guide for the clinician in deciding the amount of the desired retention between castings and abutments.


Asunto(s)
Implantes Dentales , Retención de Prótesis Dentales , Cementos de Ionómero Vitreo/química , Cemento de Policarboxilato/química , Cemento de Fosfato de Zinc/química , Cementación , Cementos Dentales , Retención de Prótesis Dentales/métodos , Prótesis Dental de Soporte Implantado , Análisis del Estrés Dental/instrumentación , Humanos , Ensayo de Materiales , Cementos de Resina , Propiedades de Superficie , Óxido de Zinc
4.
Int J Nanomedicine ; 15: 4755-4762, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32753864

RESUMEN

Aim: This study was conducted to evaluate the effects of three nanoparticle solutions used as dentin pretreatments on the microshear bond strength (µSBS) of a conventional glass ionomer cement (GIC) to dentin. Materials and Methods: Ninety intact human molars were used after sectioning their occlusal surfaces to expose flat dentin surfaces. The specimens were randomly assigned to nine groups (n = 10). Group A was the control group (without using the cavity disinfectant). In groups B, C, D, and E, the prepared dentin surfaces were treated with 1 cc 2% chlorhexidine (CHX), 0.1% silver nanoparticle (SNP), 0.1% titanium dioxide nanoparticle (TNP), and 0.1% zinc oxide nanoparticle (ZNP) solutions for 1 minute, respectively, before applying the conditioner. CHX, SNPs, TNPs, and ZNPs were applied for 1 minute after applying the conditioner in groups F, G, H, and I, respectively. The specimens were restored with a conventional GIC and underwent µSBS testing after 24 hours. The data were analyzed using the one-way analysis of variance and Tukey's test (p=0.05). Results: The applications of the nanoparticles (SNP, TNP, and ZNP) after the conditioner were associated with significantly greater µSBS values compared to that of the control group (p values < 0.05). Significantly higher µSBS values were observed when TNP or ZNP was applied after the conditioner compared to their applications before the conditioner (p values < 0.05). The highest µSBS values were observed when TNP was applied after the conditioner. Conclusion: Dentin pretreatment with the nanoparticles after applying the conditioner enhanced the bond strength of the GIC to dentin compared with the control group. The best results were obtained for the TNPs applied after the conditioner.


Asunto(s)
Recubrimiento Dental Adhesivo , Dentina/efectos de los fármacos , Cementos de Ionómero Vitreo/farmacología , Nanopartículas del Metal/química , Plata/farmacología , Titanio/farmacología , Óxido de Zinc/farmacología , Clorhexidina/farmacología , Cementos de Ionómero Vitreo/química , Humanos , Ensayo de Materiales , Propiedades de Superficie
5.
Niger J Clin Pract ; 23(7): 957-964, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32620725

RESUMEN

Aim: The aims of this study were to evaluate the surface morphology and surface roughness of restorative materials containing glass ionomer, analyze Streptococcus mutans biofilm formation on the surface of materials, and determine the correlation between surface roughness and biofilm. Materials and Methods: Four restorative materials: resin-modified glass ionomer; giomer; amalgomer; and glass carbomer were used and for each material, 6 mm in diameter and 2 mm in thickness disc-shaped specimens were prepared to evaluate the surface morphology (n = 3), surface roughness (n = 16), and biofilm (n = 20). Surface morphology was analyzed with a scanning electron microscope. Surface roughness was evaluated via an atomic force microscope. The biofilm was evaluated by counting the colony-forming units. Surface roughness measurements were evaluated using a one-way analysis of variance and Tukey HSD test. Biofilm parameters were analyzed using the Kruskal-Wallis H and Mann-Whitney U test. Pearson's correlation test was used to determine the correlation between surface roughness and biofilm. Results: While the highest roughness values were obtained for amalgomer and glass carbomer, the lowest roughness values belonged to giomer and resin-modified glass ionomer. Statistically significant differences in the number of adherent bacteria were observed between the materials only on day 1. No statistically significant correlation was determined between surface roughness and biofilm. Conclusions: The resin content and small filler particle size of material positively affect surface roughness. However, there is no direct relationship between surface roughness and biofilm.


Asunto(s)
Apatitas/química , Biopelículas/crecimiento & desarrollo , Resinas Compuestas/farmacología , Placa Dental/prevención & control , Cementos de Ionómero Vitreo/química , Streptococcus mutans/crecimiento & desarrollo , Resinas Acrílicas , Resinas Compuestas/química , Placa Dental/microbiología , Restauración Dental Permanente , Humanos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Dióxido de Silicio , Streptococcus mutans/efectos de los fármacos , Propiedades de Superficie
6.
Acta Odontol Latinoam ; 33(1): 27-32, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32621596

RESUMEN

The aim of this study was to assess the influence of different pre-treatment approaches on glass ionomer cement (GIC) bond strength (BS) to dentine. Sixty bovine incisors were allocated into six groups according to substrate - sound or caries-affected dentine; and substrate pre-treatment approach - no conditioning (control), polyacrylic acid for 10 s and phosphoric acid for 7 s. Teeth in the caries-affected dentine group were previously submitted to cariogenic pH-cycling challenge. After dentine pre-treatment, according to experimental groups, polyethylene tubes were placed on flat dentine surfaces and filled with GIC. Teeth were stored in distilled water for 24 h at 37 °C and then submitted to microshear test (0.5 mm/min). Failure pattern analysis was performed under stereomicroscope (400x). Data were analysed using two-way ANOVA and Tukey's test (α=5%). Statistically significant differences were found for the pre-treatment approach, regardless of substrate (p<0.001). The polyacrylic acid group and control group had similar BS values, and were both better than the phosphoric acid group. In general, GIC had better bonding performance in sound dentine than in caries-affected dentine. In conclusion, dentine pre-treatment with polyacrylic acid did not improve the performance of GIC restoration on clinically relevant substrates.


Asunto(s)
Resinas Acrílicas/farmacología , Recubrimiento Dental Adhesivo/métodos , Dentina/efectos de los fármacos , Cementos de Ionómero Vitreo/química , Animales , Bovinos , Filtración Dental/prevención & control , Dentina/diagnóstico por imagen , Dentina/patología , Ensayo de Materiales
7.
Arch Oral Biol ; 117: 104777, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32592930

RESUMEN

OBJECTIVE: To clarify the fluoride/mineral kinetics in an oral biofilm following concurrent application of fluoride and other mineral ions released from experimental toothpaste containing S-PRG filler using depth-specific analysis. STUDY DESIGN: Twenty subjects wore in situ plaque-generating devices, comprised of a pair of enamel slabs, and a biofilm was allowed to form. The devices were removed after three days, immersed in the toothpaste filtrate containing Al, B, Sr and F ions for 1 min, and then reinserted at the same location. After 30 min, the devices were removed and samples were obtained by sectioning into outer, middle and inner biofilm layers (300-µm thick). Samples treated with filtrate containing F without S-PRG filler extract served as the control. Fluoride and the three other mineral ions extracted from 4-µm sections were quantified using a fluoride electrode and ICP-AES, respectively. The results were corrected for biomass volume, estimated by the area measurement of stained 2-µm sections. RESULTS: The mean uptake ratios (S-PRG/control, ng/mm3) of Al, B, Sr and F were 186.6/53.7, 58.4/25.0, 456.9/125.7 and 43.6/12.0, respectively, in the outer layer, indicating that the mineral ions could easily diffuse into the biofilm. F concentrations in the outer biofilm treated using filtrate with S-PRG filler extract were significantly higher than those in controls, although both biofilms were exposed to filtrates containing the same level of F. CONCLUSIONS: The results suggest that toothpaste containing S-PRG filler promotes fluoride retention in oral biofilms via the uptake of other mineral ions.


Asunto(s)
Biopelículas , Placa Dental , Fluoruros/metabolismo , Cementos de Ionómero Vitreo/química , Minerales/metabolismo , Pastas de Dientes/química , Esmalte Dental , Placa Dental/tratamiento farmacológico , Humanos
8.
Braz Oral Res ; 34: e053, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32578763

RESUMEN

The objective was to evaluate the compressive strength (CS), diametral tensile strength (DTS), flexural strength (FS), and Knoop microhardness (KH) of different conventional restorative glass-ionomer cements (GICs) and to correlate these mechanical properties (MP) with the stabilization time (ST) of their chemical bonds. Eighteen GICs were tested: Bioglass [B], Chemfil Rock [CR], Equia Forte [EF], Gold Label 2 [GL2], Gold Label 9 [GL9], Glass Ionomer Cement II [GI], Ionglass [IG], Ion Z[ IZ], Ionomaster [IM], Ionofil Plus [IP], Ionostar Plus [IS], Ketac Molar Easymix [KM], Magic Glass [MG], Maxxion R [Ma], Riva Self Cure [R], Vidrion R [V], Vitro Fil [VF] and Vitro Molar [VM]. The mechanical strength tests were performed in a universal testing machine. KH readings were done with a diamond indenter. STs were examined by Fourier Transform Infrared spectroscopy (FTIR). Data were analyzed with ANOVA and Tukey test (p<0.05). The Spearman rank test was used to evaluate the dependence between the MPs and ST results. The highest MP values were EF, GL2, GL9, GI and KM and the lowest for MG, MA, B, VF and IM. The longest ST was for GL2 and the shortest was for B. ST correlated positively with MP. GICs with longer chemical bonds ST are generally stronger and the ST value obtained from FTIR was useful in predicting the strength of GICs tested.


Asunto(s)
Cementos de Ionómero Vitreo/química , Auto-Curación de Resinas Dentales/métodos , Análisis de Varianza , Fuerza Compresiva , Resistencia Flexional , Pruebas de Dureza , Ensayo de Materiales , Valores de Referencia , Reproducibilidad de los Resultados , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción , Factores de Tiempo
9.
Niger J Clin Pract ; 23(5): 610-618, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32367866

RESUMEN

Objective: The purpose of this study was to evaluate the effects of different pediatric drugs and toothbrushing on color changes of restorative materials used in pediatric dentistry. Materials and Methods: Sixty specimens were prepared from each of three restorative materials (compomer [Dyract XP], glass hybrid [Equia Forte], and glass carbomer [GCP Glass Fill]). Specimens were divided into six solution groups (n = 10) and immersed in five different pediatric drugs (antibiotic, analgesic, common cold syrup, cough syrup, and an iron and vitamin formula) and distilled water. Two subgroups (brushed and unbrushed) were established for each group (n = 5). Specimens were agitated for 1 min every 8 h over 2 weeks. Color changes [CIEDE2000 (ΔE00)] were calculated at baseline, 7, and 14 days. Data were subjected to 4-factor mixed-design ANOVA using a general linear model procedure for repeated measurements. Results: After 14 days, the highest ΔE00was found in the compomer/non-brushing group immersed in iron and vitamin formula (5.6 ± 0.27), and the lowest was in glass hybrid/brushing group immersed in distilled water (0.59 ± 0.8) pairwise. ΔE00values were significantly greater for compomer than for glass hybrid or glass carbomer (P < 0.05). There were statistically significant differences between the brushing and non-brushing groups for all tested solutions on the compomer specimens (except antibiotic) and glass hybrid specimens (except antibiotic and cough syrup). The Δ00 values in brushing groups were significantly lower statistically than in non-brushing groups (P < 0.05). Conclusions: Toothbrushing dramatically affected the color stability of the aesthetic restorative materials. The content of pediatric drugs is also an important factor for color change. Glass hybrids and glass carbomers used with their surface sealants appeared to be more resistant to staining from pediatric drug formulations than compomers.


Asunto(s)
Materiales Dentales , Restauración Dental Permanente , Cepillado Dental , Apatitas , Niño , Color , Compómeros , Estética Dental , Cementos de Ionómero Vitreo/química , Humanos , Ensayo de Materiales , Odontología Pediátrica
10.
BMC Oral Health ; 20(1): 40, 2020 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-32024501

RESUMEN

BACKGROUND: Silver diamine fluoride (SDF) solution gains increasing popularity in arresting dentine caries in clinical practice. The aim of this systematic review was to summarize the findings from laboratory studies on the influence of SDF application on the bond strength of dentine to various adhesives and to glass ionomer cements (GICs). METHODS: Two independent reviewers conducted a literature search in the databases Medline, Ovid, PubMed and Web of Science until 15th August 2019 using the search keywords ['bond strength'] AND ['silver diamine fluoride' OR 'silver diammine fluoride' OR 'SDF' OR 'silver fluoride' OR 'diamine silver fluoride']. Articles investigating the effect of SDF application on the bond strength of dentine to various adhesives and to GICs were included in this review. Information on how SDF application influenced the bond strength was extracted from the included articles. Besides, related information, e.g. test method of bond strength, concentration and brand of SDF, type of adhesive system and GIC, testing dental substrate, protocol of specimen preparation, and failure mode was also reviewed. RESULTS: A total of 13 articles were included in this review, with 8 and 6 studies investigating the effect of SDF application on the bond strength of dentine to various adhesives and to GICs, respectively. Sound dentine as well as demineralized dentine created by chemical methods, e.g. immersing in a demineralizing solution, was commonly adopted as the testing dental substrate. The microtensile bond strength (mTBS) test was the predominant method employed. However, the bond strength values had large variations among studies, ranging from <10 to 162 Mpa. Regarding the bond strength to different adhesives, 4 studies indicated that SDF application followed by rinsing with water had no significant influence. However, another 4 studies reported reduced bond strength after SDF application. Regarding the bond strength to GICs, 4 studies concluded that SDF application had no adverse impact on the bond strength. CONCLUSIONS: No solid conclusion can be drawn on the effect of SDF application on the bond strength of dentine to adhesives and to GICs due to the high degree of variation of the included studies.


Asunto(s)
Recubrimiento Dental Adhesivo , Cementos Dentales , Dentina/metabolismo , Cementos de Ionómero Vitreo/química , Compuestos de Amonio Cuaternario/farmacología , Compuestos de Plata/química , Fluoruros Tópicos/farmacología , Humanos , Compuestos de Plata/farmacología , Estrés Mecánico
11.
Braz Oral Res ; 34: e005, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32022224

RESUMEN

The purpose of this study was to evaluate the effect of ionizing radiation from high energy X-ray on fluoride release, surface roughness, flexural strength, and surface chemical composition of the materials. The study groups comprised five different restorative materials: Beautifil II, GCP Glass Fill, Amalgomer CR, Zirconomer, and Fuji IX GP. Twenty disk-shaped specimens (8x2 mm) for fluoride release and 20 bar-shaped specimens (25 x 2x 2 mm) for flexural strength were prepared from each material. Each material group was divided into two subgroups: irradiated (IR) and non-irradiated (Non-IR). The specimens from IR groups were irradiated with 1.8 Gy/day for 39 days (total IR = 70.2 Gy). The amount of fluoride released into deionized water was measured using a fluoride ion-selective electrode and ion analyzer after 24 hours and on days 2, 3, 7, 15, 21, 28, 35, and 39 (n = 10). The flexural strength was evaluated using the three-point bending test (n = 10). After the period of measurement of fluoride release, seven specimens (n = 7) from each group were randomly selected to evaluate surface roughness using AFM and one specimen was randomly selected for the SEM and EDS analyses. Data were analyzed with two-way ANOVA and Tukey tests (p = 0.05). The irradiation significantly increased fluoride release and surface roughness for Amalgomer CR and Zirconomer groups (p < 0.05). No significant change in flexural strength of the materials was observed after irradiation (p > 0.05). The ionizing radiation altered the amount of fluoride release and surface roughness of only Amalgomer CR and Zirconomer. The effect could be related to the chemical compositions of materials.


Asunto(s)
Apatitas/efectos de la radiación , Bisfenol A Glicidil Metacrilato/efectos de la radiación , Resinas Compuestas/efectos de la radiación , Fluoruros/química , Cementos de Ionómero Vitreo/efectos de la radiación , Radiación Ionizante , Circonio/efectos de la radiación , Análisis de Varianza , Apatitas/química , Bisfenol A Glicidil Metacrilato/química , Resinas Compuestas/química , Resistencia Flexional , Cementos de Ionómero Vitreo/química , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Valores de Referencia , Reproducibilidad de los Resultados , Espectrometría por Rayos X , Estadísticas no Paramétricas , Propiedades de Superficie/efectos de la radiación , Factores de Tiempo , Circonio/química
12.
Braz Oral Res ; 33: e125, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31994598

RESUMEN

Atraumatic Restorative Treatment (ART) is one of the strategies used to control dental caries; it involves hand instruments for removal of carious tissue, and restorations using high-viscosity Glass Ionomer Cement (GIC). The present controlled clinical trial aimed to evaluate the performance of low-cost GIC indicated for ART in primary teeth, compared with high-viscosity GIC, after one year of follow-up. Two-to six-year-old children with dentin caries lesions on one or two surfaces of anterior and posterior teeth were selected. The children were randomly assigned to 2 groups according to the restorative material used: G1 (control) - Ketac Molar®; G2 (experimental) - Vitro Molar®. Treatments were performed in a school setting, following the guidelines of the ART. A total of 728 restorations were performed in 243 children. Descriptive analysis and Poisson regression were applied, with a significance level of p < 0.05. After 12 months, 559 (76.8%) restorations were re-evaluated. The success rate was evaluated by the prevalence ratio (PR), associated with restorations performed in primary second molars (PR = 1.21; 95%CI = 1.03-1.42), and with small (PR = 1.35; 95%CI = 1.14-1.60) or medium cavities (PR = 1.29; 95%CI = 1.08-1.55), using Ketac Molar® material (PR= 1.07; 95%CI = 1.01-1.15), considering p < 0.05. Small or medium restorations in primary second molars performed with high-viscosity GIC (Ketac Molar®) were more successful than restorations performed with low-cost GIC indicated for ART.


Asunto(s)
Tratamiento Restaurativo Atraumático Dental/métodos , Caries Dental/terapia , Cementos de Ionómero Vitreo/química , Niño , Preescolar , Índice CPO , Fracaso de la Restauración Dental , Restauración Dental Permanente/métodos , Femenino , Cementos de Ionómero Vitreo/uso terapéutico , Humanos , Masculino , Ensayo de Materiales , Distribución de Poisson , Factores de Tiempo , Diente Primario , Resultado del Tratamiento , Viscosidad
13.
Microsc Res Tech ; 83(1): 3-9, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31603592

RESUMEN

This study aimed to use scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) to examine the elements that passed into the gastric acid solution after the application of a gastric acid erosive cycle to chitosan modified glass ionomer cement (GIC). Chitosan modified GIC samples were obtained by adding chitosan (vol/vol) of 5 and 10% to GIC for the experimental groups. These two experimental groups and a control group were subjected to gastric acid erosive treatment for 60 s six times a day for 10 days. The sample surfaces were coated with approximately 1 nm of gold to increase conductivity with the Q 150R ES device (Quorum Technologies, East Sussex, England). Surface topography images were obtained with a SEM. Besides, EDS analysis was also determined the number of elements graphically in the region where the fast electron beam hit. In the samples examined, the amount of element was determined. After gastric acid application, cracks and voids were observed on the surfaces of the samples. In the EDS analysis of the 5 and 10% chitosan modified GIC and control groups, Si, Al, Na, and F was found. It is necessary to investigate the antibacterial properties and physical properties of chitosan modified glass ionomer-free elements and fluorine ions using advanced techniques.


Asunto(s)
Quitosano/química , Ácido Gástrico/química , Cementos de Ionómero Vitreo/química , Animales , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Porcinos
14.
J Appl Biomater Funct Mater ; 17(4): 2280800019880691, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31872793

RESUMEN

METHODS: One hundred and twenty extracted human molars were allocated in eight groups (n = 15) based on surface conditioning and cement type. Specimens of groups 2 and 6 were conditioned with ECL whereas, groups 3 and 7 were treated with ECL + ethylenediamine tetra acetic acid (EDTA). Specimens in groups 4 and 8 were surface conditioned by ECL + EDTA + Tetric-N-Bond, and groups 1 and 5 were considered as control (non-surface treated). Cement build-ups were performed on the surface-treated dentin with BAC (groups 1-4) and RMGIC (groups 5-8). A universal testing machine was used to measure the SBS and the mode of failure was evaluated using a stereomicroscope. Statistical analysis was performed using an analysis of variance and Tukey's post hoc test, at a significance level of p < 0.001. RESULTS: The highest SBS values were observed in group 8, ECL + EDTA + Tetric-N-Bond + RMGIC (21.54 ± 3.524 MPa) and the lowest SBS values were displayed by group 1, with no surface treatment and BAC application (11.99 ± 0.821 MPa). The majority of failures were found to be mixed in lased dentin-treated dentin surfaces. BAC when bonded to dentin surfaces conditioned with ECL showed lower SBS in comparison to RMGIC. CONCLUSION: Conditioning of dentin with ECL and a bonding agent (Tetric-N-bond) improved bond strength scores for BAC and RMGIC. Use of EDTA improved bond strength values when bonded to BAC and RMGIC; however, this improvement was not statistically significant.


Asunto(s)
Dentina/química , Cementos de Ionómero Vitreo/química , Láseres de Estado Sólido , Ensayo de Materiales , Diente Molar , Humanos , Resistencia al Corte , Estrés Mecánico
15.
BMC Oral Health ; 19(1): 273, 2019 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-31801493

RESUMEN

BACKGROUND: The objective of our study was to compare the upper and lower surface microhardness and surface changes of Glass Carbomer Cement (GCP) and EQUIA Forte (EF) in different thickness after thermo-light curing durations and aging. METHODS: A total of 504 samples (5 mm-diameter) were prepared by using GCP-252 (GCP Dental, and Vianen, Netherlands) and EF-252 (EQUIA Forte, GC, Tokyo, Japan). Three different thickness samples (2, 4, and 6 mm) were prepared with 84 samples in each subgroup. The samples were prepared by three curing procedures (Non-exposed, 60s, 90s). Their varnishes were applied to the upper surfaces of half of each subgroup (n = 7). The upper microhardness measurements were evaluated before and after aging. To compare the effect of different thicknesses, the bottom surfaces of the samples were evaluated before aging in terms of microhardness measurements. Also, the upper surfaces were analyzed in the SEM before and after aging. RESULTS: The upper surface values of all the samples were higher than the bottom values (p < 0.05). There were no significant differences between the varnished and non-varnished samples in both materials (p > 0.05). Although this increase was not significant in some groups, temperature variations increased the surface microhardness values of both materials except for the non-exposed-varnished EF samples. The highest microhardnesses values were recorded in the non-exposed-varnished EF (125.6 ± 6.79) and unvarnished GCP (88.1 ± 7.59) samples which were thermo-light cured for 90 s before aging. The bottom hardness values were affected by thickness variations in both GCP and EF materials (p < 0.05). The sample deformations and microcracks after aging were greater than before in all the materials. Thermo-light curing in 90 s to the samples reduced the cracks in both the materials before and after aging. CONCLUSIONS: Thermal aging adversely affected the microhardness of the materials, which is important for clinical success. The thermo-light curing process improved the microhardness of the GCP group without varnish application. Varnish application increased the microhardness of the EF group without applying thermo-light curing. The microhardness of the bottom surfaces decreased with increasing thickness. The thermo-light curing did not increase the bottom surface microhardness of all the samples.


Asunto(s)
Apatitas/química , Luces de Curación Dental , Cementos de Ionómero Vitreo/química , Cementos de Ionómero Vitreo/efectos de la radiación , Resinas Acrílicas , Resinas Compuestas/efectos de la radiación , Dureza , Humanos , Japón , Ensayo de Materiales , Países Bajos , Propiedades de Superficie , Temperatura , Factores de Tiempo
16.
Braz Oral Res ; 33: e099, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31778471

RESUMEN

The aim of this clinical trial was to compare the 5-year cumulative survival of atraumatic restorative treatment restorations using high-viscosity glass-ionomer restorations (ART/HVGIC) and conventional resin composite restorations (CRT) placed in patients with intellectual and/or physical disability. Patients referred for restorative care to a special care service in Córdoba, Argentina, were recruited. Patients and/or caregivers were provided with written and verbal information regarding treatment options and selected the alternative they preferred. The treatment protocols were ART (hand instruments/HVGIC) in the clinic or CRT (rotary instrumentation/resin composite) in the clinic or under general anaesthesia (GA). Two independent, trained and calibrated examiners evaluated restoration survival using established ART codes after 6, 12, 24, 36 and 60 months. The proportional hazard model with frailty corrections provided survival estimates. Jackknife errors were used to test 5-year results. Sixty-six patients (13.6 ± 7.8 years) with 16 different medical conditions participated. CRT in the clinic proved feasible for five patients (13%), and 14 patients received CRT under GA (21%). ART was provided for 47 patients (71.2%). A total number of 298 dentine carious lesions were restored in primary and permanent teeth (182 ART; 116 CRT). Four patients died between the 3 and 5-year follow up. Percentage survival and jackknife standard error were calculated and were significantly higher for all ART/HVGIC restorations (90.2% ± 2.6) than for all CRT restorations (82.8% ± 5.3), 5 years after placement (p=0.044). These 5-year follow-up results confirm that ART/HVGIC is an effective treatment protocol for patients with disability, equal to that of conventional resin composite restoration. The results of this clinical trial support the use of ART as an evidence-based treatment resource contributing to the reduction of inequalities in access to oral health care among people with disability.


Asunto(s)
Resinas Compuestas/uso terapéutico , Tratamiento Restaurativo Atraumático Dental/métodos , Restauración Dental Provisional/métodos , Personas con Discapacidad , Cementos de Ionómero Vitreo/uso terapéutico , Adolescente , Adulto , Niño , Preescolar , Resinas Compuestas/química , Fracaso de la Restauración Dental , Femenino , Estudios de Seguimiento , Cementos de Ionómero Vitreo/química , Humanos , Masculino , Reproducibilidad de los Resultados , Factores de Tiempo , Resultado del Tratamiento , Viscosidad , Adulto Joven
17.
Biomed Mater Eng ; 30(4): 439-448, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31476144

RESUMEN

BACKGROUND: Adhesion strength of orthodontic attachments to enamel should be within optimal range to resist occlusal forces and to allow debonding without enamel damage. OBJECTIVE: The present study compared the effect of non-thermal plasma (NTP) and conventional surface treatment on the adhesion strength of orthodontic bracket to enamel. METHODS: A total of 100 premolar teeth were allocated into 5 groups according to the bonding procedure followed: Group 1 (Etch, prime and composite adhesive); Group 2 (Prime and composite adhesive); Group 3 (Glass ionomer cement); Group 4 (NTP, prime and composite adhesive) and Group 5 (NTP and glass ionomer cement). Ten specimens in each group were subjected to artificial aging and the remaining ten specimens served as baseline specimens. Adhesion strength values were recorded after debonding and bond failure types were scored. Water contact angles of the NTP treated and untreated enamel surface were measured. RESULTS: Group 1 specimen demonstrated highest bond strength at baseline (21.5 ± 3.01) and thermocycling (15.8 ± 2.87) and the least values were in Group 2 specimens at baseline (3.9 ± 1.01) and thermocycling (1.6 ± 0.7). Among the experimental (NTP) groups, Group 4 specimens exhibited high adhesion strength at baseline (10.2 ± 1.76) and after thermocycling (9.8 ± 2.15) compared to Group 5 specimens at baseline (10.1 ± 1.05) and thermocycling (6.5 ± 2.19). The water contact angle on untreated enamel surface was 53.1° ± 2.1° as compared to 1.4° ± 0.7° in treated surface. CONCLUSION: Non-thermal plasma (NTP) treatment in conjunction with composite adhesives demonstrated clinically acceptable adhesion strength and was well within the optimal range (7-14 MPa) for enamel bonding.


Asunto(s)
Adhesivos/química , Esmalte Dental/química , Soportes Ortodóncicos , Adhesividad , Análisis del Estrés Dental , Retención de Dentadura/efectos adversos , Cementos de Ionómero Vitreo/química , Humanos , Ensayo de Materiales , Soportes Ortodóncicos/efectos adversos , Gases em Plasma , Cementos de Resina/química
18.
J Ayub Med Coll Abbottabad ; 31(3): 418-421, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31535519

RESUMEN

BACKGROUND: This study was conducted to compare the adaptation of resin-based sealants with that of Resin modified glass ionome-based sealants in various tooth fissure morphologies. METHODS: It was an in vitro experimental study done at the Dow University and NED University, Karachi, Pakistan. Ten extracted human molars were randomly assigned to two groups, (n=5) each. Fissure sealant material (Resin based sealant or resin modified glass ionomer-based sealant) was applied on the occlusal surface of the tooth according to manufacturer's recommendations. Specimens were thermocycled and then sectioned into three longitudinal parts in the bucco- lingual direction. Specimens were examined using scanning electron microscope for the adaptation of the sealant in the occlusal fissure. Mann-Whitney -U test and Kruskall-Wallis test were applied to compare the adaptability scores of sealant materials in the tooth fissure. Level of significance was kept at 0.05. RESULTS: There were no significant differences in the adaptability scores among U-shaped (p-value=0.35), V-shaped (p-value=0.89), IK-shaped (p-value=0.52), I-shaped (p-value- =0.41) and Y-shaped (p-value=1.00) fissure patterns. Similarly, there were no significant differences observed between the resin-based sealant (p-value=0.95) versus RMGIC based sealant (p-value=0.63) for the adaptability scores in various tooth fissure morphologies. CONCLUSIONS: No significant difference was found between resin-based sealants and resin modified glass ionomerbased sealants for the adaptation in various tooth fissure patterns.


Asunto(s)
Fisuras Dentales/patología , Cementos de Ionómero Vitreo , Diente Molar , Selladores de Fosas y Fisuras , Cementos de Ionómero Vitreo/química , Humanos , Diente Molar/efectos de los fármacos , Diente Molar/patología , Pakistán
19.
PLoS One ; 14(8): e0220718, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31430298

RESUMEN

A series of experiments were conducted to characterize a novel restorative material. We explored the effect on biological, physical and chemical properties of glass ionomer cement (GIC) adding-the naturally occurring tt-farnesol (900 mM). Two groups were accomplished for all assays: GIC+tt-farnesol and GIC (control). Biological assays: 1) agar diffusion against some cariogenic bacteria; 2) S. mutans biofilm formation and confocal laser scanning microscopy-CLSM. 3) gtfB, gtfC, gtfD, gbpB, vicR, and covR expression; 4) MTT and microscopic morphology. Physical properties assays: 1) roughness; 2) hardness; 3) compressive strength and 4) diametral tensile strength. Chemical assay: Raman spectroscopy. The adding of tt-farnesol to GIC led to larger zones of inhibition (p<0.05), biofilms with a short-term reduction in bacterial viability but similar biomass (p>0.05). Polysaccharides levels increased over time, similarly over groups (p>0.05). Viable and non-viable S. mutans were seen on the specimens' surface by CLSM but their virulence was not modulated by tt-farnesol. The tt-farnesol increased the HaCaT cell viability without impact on compressive and diametral tensile strength and roughness although the hardness was positively affected (p<0.05). Raman confirmed the presence of tt-farnesol. The incorporation of tt-farnesol into GIC inhibited the growth of cariogenic bacteria but had a little effect on the composition, structure and physiology of the biofilm matrices. Also, the tt-farnesol increased the hardness and the biocompatibility of the GIC, not influencing negatively other physical properties of the restorative material.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Farnesol/análogos & derivados , Farnesol/farmacología , Cementos de Ionómero Vitreo/química , Cementos de Ionómero Vitreo/farmacología , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Dureza , Humanos , Ensayo de Materiales , Viabilidad Microbiana/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/fisiología , Resistencia a la Tracción
20.
Photodiagnosis Photodyn Ther ; 28: 110-113, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31419580

RESUMEN

AIM: The aim of this in-vitro study is to investigate the shear bond strength (SBS) of Bioactive bulk fill restorative material (BARM) (Activa) by surface pre-treatment using Er,Cr:YSGG (ECL) on dentin in comparison to conventional dentin conditioning techniques. MATERIAL AND METHODS: Sixty extracted non-carious, non-fractured, restoration free human molars were collected and mounted vertically in acrylic resin. The buccal surface of all molars were ground and polished with abrasive paper. The specimens were randomly allocated into four groups (n = 15) according to the type of surface treatment. Group 1 ECL + BARM, Group 2 ECL + Ketac + BARM, Group 3 Conventional Etch and Rinse + BARM, Group 4 Self-etch + BARM. The specimens from each group were positioned in a universal testing machine for SBS testing. Ten samples from each group were assessed for modes of failure. Means and standard deviations were compared using analysis of variance (ANOVA) and Tukey's post hoc test at a significance level of p < 0.05. RESULTS: BARM bonded to dentin surface etched with conventional etch and rinse technique (group 3) exhibited SBS value of 18.45 ±â€¯1.34. Similarly, the lowest bond strength was observed by group 4 (self-etch regime) bonded to BARM (16.09 ±â€¯0.81). The bond strength among groups 1 (ECL + BARM), 2 (ECL + Ketac + BARM) and 3 (etch and rinse + BARM) were found to be comparable (p > 0.05). CONCLUSION: Conditioning of dentin with photobiomodulation for the adhesive bonding of BARM showed comparable bond strength outcomes to conventional conditioning techniques.


Asunto(s)
Resinas Compuestas/química , Recubrimiento Dental Adhesivo/métodos , Cementos de Ionómero Vitreo/química , Láseres de Estado Sólido , Grabado Ácido Dental , Análisis del Estrés Dental , Humanos , Técnicas In Vitro , Ensayo de Materiales , Diente Molar , Resistencia al Corte , Propiedades de Superficie
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